There's something to be said for all of them. I have vaginismus (my pussy essentially spasms shut when I try to put anything in it), so regular-vanilla is an intensely painful experience for me these days. I can take a dick there and even enjoy it, but you really need to be kind of a sadist.
Anal has a weird effect on me, over and above being painful and so on. Being fucked there makes me VERY submissive; even done with care, it's like this complete trauma that destroys all of my resistance. For some reason I cum very easily from anal -- need clitoral stimulation as well, but anal makes me go off like a rocket. It's very easy for someone to force an orgasm out of me by taking my ass and playing with my clit; after a few minutes, I'm cumming like a slut on my ravisher's cock.